On-body Sensing Systems: Motion Capture for Health Monitoring

On-body sensors capture quantitative data from variety of bio-signals on a subject’s body with applications in health, sports and entertainment. With the increase in health costs, a need has arisen to monitor a patient’s condition out of hospital in a costeffective way. In healthcare applications on-body sensing systems can provide feedback information about one’s health condition either to the user or to a medical centre. They can also be used for managing and monitoring chronic disease, elderly people, and rehabilitation patients. In rehabilitation applications, such systems can be used to capture patient movement and monitor progress or provide feedback to enhance patients’ motor learning and increase rehabilitation effectiveness. Human motion capture systems are expected to generate motion data through several techniques that dynamically represent the posture changes of a human body based on motion sensor technologies. In motion analysis, the human body is typically modelled as a system of rigid links connected by rotary joints. In this paper after describing body models and their approximation by link-segment models, we introduce kinematics and inverse kinematics problems for determining motion. Different sensor technologies and related motion capture systems are then discussed. It is shown how motion data is derived from position and orientation for the different motion capture technologies